Atomic Structure
This is the dense, positively charged center of an atom
What is the nucleus
This number indicates the total number of protons in an atom's nucleus
What is the atomic number
This term describes the spontaneous emission of particles from an unstable nucleus
What is radioactive decay
This word means the smallest unit of an element retaining its properties
What is an atom
In atomic diagrams, this number reflects the sum of protons and neutrons
What is the mass number
These subatomic particles are found in the nucleus and have no charge
What are neutrons
This is the weighted average mass of an element's naturally occurring isotopes
What is atomic mass
A reaction where two smaller atoms combine to form a larger atom, typically in stars
What is nuclear fusion
These are particles with a positive charge found within an atom's nucleus
What are protons
These diagrams show the distribution of electrons around an atom’s nucleus
What are Bohr diagrams
The force that keeps the nucleus stable by holding protons and neutrons together
What is the strong nuclear force?
An element with more protons and neutrons than is stable can emit particles in this process
What is radioactivity
Atoms of the same element with different numbers of neutrons are called this
What are isotopes
This force of attraction and repulsion occurs between charged particles in an atom
What is electromagnetic force
These are the fundamental particles that make up protons and neutrons
What are quarks
These particles are located in the electron cloud surrounding the nucleus
What are electrons
The atomic number of this element is always 19, as it is represented by the symbol K
What is potassium
The amount of time it takes for half of a radioactive substance to decay
What is a half-life
This term describes an atom that has lost or gained electrons and carries a charge
What is an ion
The type of energy level shell that valence electrons occupy in atomic diagrams
What is the outermost shell
The area within an atom where electrons move in constant motion, defining its volume
What is the electron cloud
These elements, found in Group 18, are known for their lack of reactivity
What are noble gases
This type of nuclear reaction results in the formation of new elements in stars
What is nucleosynthesis
The term for the emission of rays or particles during a nuclear reaction
What is radiation
In nuclear notation, this is shown as a superscript next to the element symbol
What is the mass number